The triple-probe method applied to the direct display of plasma parameters in a supersonic flowing continuum plasma

Abstract

The calibration of electrostatic triple-probe voltage and current response in a supersonic continuum plasma has been carried out using a low-pressure shock tube. The electron temperature Te and charge number density Ne are compared to probe voltage and current response, respectively, for a useful range of plasma parameters (1≲Rp/λD≲10, 2≲M≲5, and 7<φ13<35, where Rp is the probe radius, λD is the Debye length, M is the shock Mach number, and φ13 is the nondimensional probe voltage). The dependence of probe response on Debye ratio Rp/λD and various flow parameters was investigated. The probe voltage response was found to depend significantly on the Debye ratio. Expressions for electron temperature determination by triple probe are presented.